Ship form



April 5, 1938. H. K. KLoEss 2,113,465

' SHIP FORM 'Filed March 7, `1936 3 sheets-sheet .1L

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April 5, 1938.- H K KLQl-:SS 2,113,466

- SHIP FORM Filed March 7, 1936 3 Sheets-Sheet 2 IIIII [Wren/0f:

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April 5, 1938. n H. KKLQESSI `2,113,466

SHIP FORM Filed March 7, 1956 sheets-sheet 5 Patented Apr. 5, 1 938 UNITED `STATES PATENT OFFICE Application March 7,

1936, serial No. 67,605

In Germany December 17, 1935 4 Claims.

My invention relates to `ships and their .construction. Thesubject-matter of the present invention deals with a ship form ,known asthe Maier vform as shown for .example in Patents 1,729,446 and1,737,886, and ismore particularly concerned with the part of the hull-above the water line as illustrated in the accompanying drawings invarious embodiments.

Fig. l is a bow elevation of a ships form according to an embodiment ofthe invention.

Fig. 2 is a side elevation of Fig. l.

Fig. 3 is a diagram of the curve connecting the centers of areas of thehalf waterline surfaces of a form according to the invention in Fig. 1.

Figs. 4 to 6 and 7 to 9 each inclusive are respectively views ofdiierent embodiments of the invention the figures each taken in mannerset forth for Figs. 1 to 3 inclusive.

Fig. 10 is a diagram of the curve connecting the centers of areas ofhalf waterline surfaces of a Maier form of ships hull.

As is known a Maier form bow has an approximately triangular beamcross-section in combination with an obliquely rising stem contour as,for example, shown in Figs. 3 and 4 of Patent 1,729,446. 'I'hus theMaier form bow is formed of two obliquely disposed straight, or more orless curved, surfaces coming together at an oblique angle in the stemline and the point entry of the stem on the water line characteristic ofthe Maier form is achieved. These properties of the Maier form are shownparticularly clearly by the curve of the connecting lines of the centresof area of the half water line surfaces as illustrated in Figure 10.

Practical experiences and theoretical investigatons have demonstratedthe fact that the known great advantages of the Maier form are due in aconsiderable measure to the fact that in consequence of the uniform andcontinuous increase of the displacement in the part of the ship abovewater line, as shown clearly by Figure 10; the downward movements of theforepeak in rough weather are strongly braked. The centre point of thepitching movements of the Maier form ship in comparison with theso-called normal form ships is moved further toward the stern whichgives a steadier position of the stern, which in turn results in abetter operation of the driving arrangements in rough weather.

These discoveries form the basis of the present invention, which setsout to solve the problem of improvingthe behaviour of any desired bowconstruction in heavy weather.

According to my invention I accomplish this by forming vthe linesjoining the centres of area of the half water lines from the region ofthe load water line upwards according to the shape of the line ofAcentres ofnarea Yof the Maier Aform shown in Figurejlll, while inthepart below'the water line the curve of these lines of centres of arearemains substantially that determined by the cross-section constructionof the ship used in the under-water part. Thereby the fore-part of theship in the range of the intersection of the front stem-line with theconstruction water line will be given a V-shape, the frames being eitherstraight or slightly curved, whereas the other frame-portions of theforepart of the ship above the water line, for a certain length bothtoward the bow and toward midships, are disposed substantially parallelwith the frames of the V-section. Thus the advantages of any desiredunder-water shapes of ships achieved in the smooth water of theexperimental tank can be maintained in rough weather without substantialreduction because the pitching movements of such a ship are considerablybraked by the additional displacement according to the Maier form givento the part of the ship above the water line.

In Figures 1 and 2 the known form of 'a bulging bow ship is indicated bythe dotted lines, while the full lines show the shape of the forwardpart of the ship according to this invention.

Figure 3 sho-ws how the new ship form is developed. The dotted line inFigure 3 represents the line of centres of area of a normal bulge bowship. This line, according to the present invention, is deflected belowthe water line from its normal shape so that in the region of the loadline it has an inclination in which a tangent drawn to it here enclosesan angle of at most 70, or less, with the horizontal. This shape of theline of centres of area should be maintained as far as possible for thewhole height of the hull up to the highest point of the deck orfore-castle.

A ship thus constructed combines the characteristic properties of abulge bow ship with the advantageous properties of a Maier form ship inrough weather. While many bulge bow forms not only lose in rough weatherthe gain achieved in smooth water because of a reduced resistance butoften even behave worse than a normal ship, by the present invention Iachieve the result that bulge bow ships retain even in rough weathertheir advantageous properties, in particular with respect to theirreduced resistance.

Figures 4 to 6 show that in the same way the properties of a normal shiphaving vertical crosssectons below the Water line can be improvedaccording to this invention by a corresponding construction of the abovewater portion of the fore part. In these iigures also the dotted linesshow the normal form, while the full lines in Figures 4 and 6 show themodified construction embodying the present invention.

Figures 7 to 9 show a fore part in which the setting of thecross-sections is determined by the direction of radii from a commoncentre P below the keel line of the cross-section as shown in Figure 7.Here again the full lines show the construction of the part of the shipsform above the water embodying the present invention.

The present invention makes it possible to combine to a great extent ina single form all the advantages determined hitherto by scientificmeasurements and by observations in practice in different ship forms.

What I claim is: K

1. In the construction of the fore-part of a ships hull above the waterline, in combination with the slanting r'o'n't stem, frame sections ofV-shape starting from the intersection of the slanting front stem linewith the water-line, said frame-sections throughout a portion of thefore-part both toward the bow and toward midships being disposedparallel with the substantially straight frames within the range of saidV-shaped frame sections, a tangent drawn upwards from the bottom line tothe line connecting the centres of area of the half water linesenclosing in the neighborhood of the load line with the Water line anangle of about 70, While the line connecting the centres of areamaintains its inclination over a material portion of the height of thefore-part above the water line.

2. The construction as specified in claim 1, in which the portion of thefore-part below the water line is of the bulge-bow form.

3. The construction as specified in claim 1, in which the frame lines ofthe fore-part below the water line are substantially vertical.

4. The construction as speciiied in claim 1, in which the direction ofthe frame lines in the portion of the fore-part below the water-line isdetermined by radii from a point below the bottom line.

HANS KARL KLOESS.

